kernel-ark/fs/gfs2/meta_io.h
Steven Whitehouse f91a0d3e24 [GFS2] Remove useless i_cache from inodes
The i_cache was designed to keep references to the indirect blocks
used during block mapping so that they didn't have to be looked
up continually. The idea failed because there are too many places
where the i_cache needs to be freed, and this has in the past been
the cause of many bugs.

In addition there was no performance benefit being gained since the
disk blocks in question were cached anyway. So this patch removes
it in order to simplify the code to prepare for other changes which
would otherwise have had to add further support for this feature.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2008-01-25 08:07:16 +00:00

77 lines
2.3 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#ifndef __DIO_DOT_H__
#define __DIO_DOT_H__
#include <linux/buffer_head.h>
#include <linux/string.h>
#include "incore.h"
static inline void gfs2_buffer_clear(struct buffer_head *bh)
{
memset(bh->b_data, 0, bh->b_size);
}
static inline void gfs2_buffer_clear_tail(struct buffer_head *bh, int head)
{
BUG_ON(head > bh->b_size);
memset(bh->b_data + head, 0, bh->b_size - head);
}
static inline void gfs2_buffer_copy_tail(struct buffer_head *to_bh,
int to_head,
struct buffer_head *from_bh,
int from_head)
{
BUG_ON(from_head < to_head);
memcpy(to_bh->b_data + to_head, from_bh->b_data + from_head,
from_bh->b_size - from_head);
memset(to_bh->b_data + to_bh->b_size + to_head - from_head,
0, from_head - to_head);
}
struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp);
void gfs2_aspace_put(struct inode *aspace);
void gfs2_meta_inval(struct gfs2_glock *gl);
void gfs2_meta_sync(struct gfs2_glock *gl);
struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno,
int flags, struct buffer_head **bhp);
int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh);
void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
int meta);
void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr,
int meta);
void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen);
int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
int new, struct buffer_head **bhp);
static inline int gfs2_meta_inode_buffer(struct gfs2_inode *ip,
struct buffer_head **bhp)
{
return gfs2_meta_indirect_buffer(ip, 0, ip->i_no_addr, 0, bhp);
}
struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen);
#define buffer_busy(bh) \
((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock) | (1ul << BH_Pinned)))
#define buffer_in_io(bh) \
((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock)))
#endif /* __DIO_DOT_H__ */